Fast Global Alignment Kernels

Marco Cuturi

Abstract: We propose novel approaches to cast the widely-used family of Dynamic Time Warping (DTW) distances and similarities as positive definite kernels for time series. To this effect, we provide new theoretical insights on the family of Global Alignment kernels introduced by Cuturi et al. (2007) and propose alternative kernels which are both positive definite and faster to compute. We provide experimental evidence that these alternatives are both faster and more efficient in classification tasks than other kernels based on the DTW formalism.